In a special series, Tony Atherton goes to some of our city’s top architects and designers to get a sense of what could be done with the home of our prime minister

Deep rich Canadian hardwood and limestone distinguish grand formal spaces beneath a roof as skewed and staggered as a wild Canadian landscape in this concept created by Samantha Schneider of Christopher Simmonds Architect.

Large formal spaces within the design all have a river view. The dining room leads down to a sunken lounge and living room marked by a massive floating fireplace

The long, linear, single-storey great house is the least expensive of the designs. It has fewer than half the rooms of the current residence, but the scale of the formal spaces is large, and nearly all the living spaces take advantage of the dramatic view offered by the clifftop location of 24 Sussex.

Left The design features a peaked roof and lots of windows on the river side of the building, allowing views of the Gatineau Hills

“I guess it’s more residential-scale in some ways — however, the roof takes it slightly somewhere else. I think it just suits the site and the purpose,” says Schneider.

The roof line is meant to evoke a sense of Canadian geography

The design is partly instinctual, says Schneider. “This is more to do with creating landscape,” she says.

“The intention, says Chris Simmonds, “was to use forms, like the form of the roof, in a way that people could relate to.” A sloped roof is more familiar than a flat roof, he says, but a sloped roof “in the form of a crystalline composition would be understood as something that was evocative of the landscape.”

Inside, limestone and torrefied ash continue to be dominant elements. A long floating stone fireplace that marks the grand entrance can also be seen from each of the formal spaces, including the sunken living room and den.

COMPENDIUM

Living Space: 7,050 square feet on the ground floor plus 6,350 square feet in the basement.

Cost: $3.877 million, not including extraordinary security measures.

Materials: Canadian elements predominate. The dramatic roofline is clad in long-lasting zinc and faced on the underside with torrefied ash. The limestone base is re-dressed stone from the original building.

Environment: The roof projects to the south and folds along the west side to increase shading, ground-source heat pump for heating/cooling, triple glazing in windows, possible thin-film solar cells on metal roof.

Outbuilding: The design assumes an outbuilding that serves as a garage and service quarters. A 2,000-square-foot outbuilding would add $900,000 to the budget. A basement provides space for storage and mechanical services.